1. Field
The present disclosure relates to radiation treatment and more particularly, to an apparatus and method that allows cancer patients to receive a low dose radiation treatment after removal of a tumor.
2. Description of Related Art
Today, a number of treatment options exist for patients who are diagnosed with cancer. With respect to breast cancer, mastectomies commonly have been used. A mastectomy involves removal of all or a part of the breast tissue, and sometimes also involves removal of the underlying pectoral muscles and lymph nodes around the breasts. Mastectomies may be accompanied by significant scarring, thus adversely affecting the aesthetic appearance or cosmesis of the breast and surrounding tissue. Moreover, removal of all or large regions of the breast may have an associated significant physical trauma as well as psychological trauma.
Various alternative treatment options have been developed to address adverse affects associated with mastectomies. These alternative treatment options may involve a breast-sparing lumpectomy. A lumpectomy tends to involve removal of only the portion or “lump” of the breast that contains tissue having tumors. The remaining tissue outside the removed lump may be treated subsequently with breast irradiation that is designed to treat abnormal or suspect tissue that surrounds the removed tumor.
One of the various lumpectomy options involves full breast irradiation. While this option incorporates the breast-sparing lumpectomy, the treatment time may last for several weeks, with several treatments a day during those weeks. At times, the number of treatments may be as much as thirty treatments. Such a high number of treatments may be not only inconvenient for the patient, it may also be expensive since each time the patient sees a doctor, a charge may follow. Even for insured patients, all of the charges may not be covered by the patient's insurance.
Moreover, lumpectomies involving full breast irradiation may result in significant surface tissue damage of healthy tissue since the entire breast is being irradiated. Likewise, the cosmesis or aesthetic appearance of the breast may be compromised since the entire breast is being irradiated. Moreover, because more tissue is affected, the risk of complications may increase with full breast irradiation.
In order to address the consequences of full breast irradiation procedures, partial breast irradiation procedures have been developed. These options may incorporate high dose radiation. With high-dose irradiation, significant patient discomfort may result since multiple needles and catheters are placed into the breast. Moreover, there is a greater chance that surface tissue damage may occur, resulting in scarring and sensitivity due to the use of the multiple needles and catheters.
Another example of a treatment option that has been developed incorporating partial breast irradiation is one developed by Proxima Therapeutics, Inc., and known as the MAMMOSITE™ radiation therapy treatment system. This system appears to be designed to address some of the drawbacks associated with full breast irradiation while also addressing some of the drawbacks associated with high-dose radiation. The procedure involves inflating a balloon so that it fills the empty cavity and inserting a high-dose radiation source for delivery inside the cavity. The treatment time may be twice a day for five (5) days, for a total of ten (10) treatments. However, the patient selection criteria may be limited in that patients with small breasts may not be good candidates. For example, the breast may be too small to allow proper inflation of the balloon since the balloon relies on air for expansion.
Recently, brachytherapy has been used for partial breast irradiation to deliver a more localized treatment of tumor cells after a lumpectomy. Partial breast irradiation is used to supplement surgical resection by targeting the residual tumor margin after resection, with the goal of treating any residual cancer in the margin. Radiation therapy can be administered through one of several methods, or a combination of methods, including external-beam radiation, stereotactic radiosurgery, and permanent or temporary interstitial brachytherapy. Owing to the proximity of the radiation source, brachytherapy offers the advantage of delivering a more localized dose to the target tissue region.
There is a need for an instrument and associated procedure which can be used to deliver radiation from a radioactive source to target tissue with a desired intensity and without over-exposure of body tissues disposed between the radiation source and the target.
There is further a need for an instrument and associated procedure that has broad patient selection criteria with reduced office visits.
There is yet further a need for an irradiation procedure that is appropriate not only for breasts, but may be used in treatment regimens for other areas of the body, such as the brain and prostate.